A former goalkeeper at Pele's club Santos, Edinho was found guilty of drug trafficking and money laundering in 2005 but has been fighting the charges ever since.
A judge heard his appeal against the original 33-year sentence on Thursday and reduced it to 12 years and 10 months.
Edinho protested his innocence and expressed confidence that "things will work themselves out".
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"I am very frustrated because I am being accused of money laundering and I never did that, there is no evidence of that," Edinho told reporters in Santos, the city where his father made his name.
"The argument is about my friendship with the other accused, and I never denied that, but I never laundered money."
Edinho, whose full name is Edson Cholbi do Nascimento, vowed to keep fighting the charges.
His father Pele, 76, is considered the greatest player of all time and helped Brazil to win three World Cup titles.
(Reporting by Eduardo Simoes, writing by Andrew Downie; Editing by Clare Fallon)
